Day 10 – Taking User Input in Python

Welcome to Day 10 of 100 Days of Python!

Until now, most of our programs have worked with values that we directly wrote inside the code.

But what if we want the user to provide the data while the program is running?

That's where Python's built-in input() function comes in.

In this lesson, we will learn:

• How to take input from a user

• How input() works

• Why input() always returns a string

• How to take integer and float input

• How to use a prompt with input()

• How type casting works with user input

• A common mistake when performing calculations with input

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1. What is User Input?

User input is data provided by a user while a program is running.

Python provides the built-in input() function to take input from the user.

The basic syntax is:

variable = input()

For example:

name = input()

print(name)

If the user enters:

Sritesh

The output will be:

Sritesh

The value entered by the user is stored in the variable name.

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2. How Does input() Work?

When Python encounters input(), the program pauses and waits for the user to enter something.

For example:

name = input()

print("Hello, " + name)

If the user enters:

Sritesh

The program produces:

Hello, Sritesh

So the basic flow is:

Program
   ↓
input()
   ↓
User enters data
   ↓
Python receives the data
   ↓
Value is stored in a variable

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3. Important: input() Always Returns a String

This is one of the most important things to remember about input():

The input() function always returns the user's input as a string (str).